Remove extra_info argument from js_optimizer.py. NFC

[sbc100]

This had no users. The only user of run_on_file is run_js_optimizer which doesn't pass this argument.

[sbc100]

The js_optimizer tool seems like it only used for wasm2js output these days. Should we just remove it and rely on the existing closure tools etc, or is it serving some important function?

[kripken]

We use js_optimizer passes to process the JS for metadce (before and after) and our own emscripten-specific JS optimizations, I think?

[sbc100]

We use js_optimizer passes to process the JS for metadce (before and after) and our own emscripten-specific JS optimizations, I think?

I think we use acorn_optimizer in all cases except wasm2js. IIUC wasm2js is the only user of js_optimizer.py

[kripken]

Oh, I forgot that distinction. Yes, maybe we can remove this, then.

[kripken]

(depending on how well the replacement performs, of course)